Sewing machine



Jan. 22 1924. 1,481,514

J. KIEWICZ SEWING MACHINE Filed Aug. 8, 1.922 2 Sheets-Sheet 1 Fig.1.

' !nvenToT. I John Kiewicg SEWING MACHINE Filed Aug. 8, 1.922 2 Sheets-Sheet 2 ,22 v I A. r u

/ lnvenTor I John Kiewicg b mwkw A1Tys.

Patented Jan. 22, 1924.

UNITED STATES PATENT OFFICE.

J'OHN KIEWIGZ, OF BOSTON, MASSACHUSETTS,ASSIGNOR TO THE BEECE BUTTON HOLE MACHINE COMPANY, 013 BOSTON, MASSACHUSETTS, A CORPORATION OF MAINE.

SEWING MACHINE.

Application filed August 8,

T 0 all whom it may concern Be it known that I, Jenn liniwioz, a citizen of the United States, and resident of Boston, county of oufiolk, State of Massachusetts, have invented an Improvement in Sewing Machines, of which the following description, in connection with the accom panying drawing, is a specification, like charactersonthe drawing representing like parts.

This invention relates to button-hole sewingmachines and particularly to the workclamps thereof, and theobject off the inventionis'to provide a novel'means for controlling the spreading action of the workclamps after the button-hole slit has been w,

Some'button-hole sewing machines are arranged so that whenlthey are-started in operation the button-hole cutter'is first oper-' ated'to cut the botton-hole slit, after which there is a relative movement between the work-holding means 'andfithe stitch-forming mechanism to bring the parts from buttonhole cutting'positi'on into stitching position, and the stitch-forming mechanism is then setin' operation to stitch around the edges of the'button-hole. It is customary to constr'uctthe work-clamping means sothat during the movement from button-hole cutting to stitching positionthe worlris stretched slightly transversely of the slit, thereby to spread or open the latter. My present invention relates to a device for this purpose and has particular reference to means for controlling" the amount which the button-hole slit will be spread at any operation. p In order to give an understanding of my invention, Ihave illustrated in thedrawings a selected embodiment thereof, which will now be described, after which the novel fea-. tures will be pointed out in the appendedclaims. V.

In the drawings, Fig.1, shows asuflicient portion of a button-hole sewing machine to illustratethe construction and operation of my invention, said figure beinga plan view ofthe' work-holding means.

Fig. 2 is an underside view of the front portion'of the bed frame illustrating part of the control mechanism. 1

In thedrawings, 1 indicates :the front portion of the bed frame of a button-hole sewing machine. This is formed at 2 to receive 1922.' Serial No. 580,571.

the two clamp-plates 3 and 4. Each clamp plate is provided with a roughened portion 5, said portions being situated either side ofthe sewing opening and co-operating with the work-clamp 6, for clamping the work in position. These Work-clamps 6, are carried by arms 7 that are pivoted to the clampplates 3 and 4.

In Fig. l, 8 indicates the throat plate of the under thread mechanism, and 9 indicates part of the button-hole cutter.

The parts thus far described are or may be all as usual in buttonhole sewing machines and form no part in the present invention. In the operation of these 'sew'ing machines, the workis introduced between the work-clamps 6, and the roughened surface 5 of the clamp plates, and the workclamps are then depressed to clamp the work in position.

After the machine is started, the buttonso as to open the buttonhole slit and this spreading operation is accomplished by means of a spreading member 10 having two rounded or cam surfaces 11, which co'-operat'e'with rolls 12 carried by the under side of the clamp plates. The spreadingmember 10 ismounted as usual in sewing machines of this type so that during the relative movement between the'throat plate and the Work-holding means, there will be a relative movement between the cam surfaces 10 and rolls 12 so that as the cam surfaces wipe past the rolls 12 the clamp platesare spread or separated from each other. The amount of separating movement which is givento the clamp plates in passing the cam surfaces 11, depends upon the initial position of said clamp plates relative to each other. a

If theclamp plates are initially at the limit of their movementtoward each other, thenthey have a greater spreading action as the rolls 12 pass therounded surface 11,

than it the clamp plates wererinit-ially sep arated slightly.

I have provided herein means for nor'- many-controlling the initial position of the clamp. plates and thereby determiningv the degree of spreading movement.

In the construction herein shown, each clamp plate has a plate 13, connected thereto, which is provided with a slot 14, in which operates a pin 15, secured to the end of a lever 16,- situatcd'on the underside of the bed plate. and'pivoted thereto at 17; Each lever lG'has a pivotalconnection with one end of another lever lSalso pivoted to the bed plate at 19. The other end of the two levers 18. are pivotally connected to two slides 20, that operate in ways 21 formed on the underside of the bed plate andare attached to -the clamp plates 3 and 4, by

the two screws 22; These slides 20, are con nected by spring which tends to draw them together.

With this construction it will be seen that when the levers 1618'- of either pair are turned'so as to swing them more nearly into line with each other, as illustrated in Fig. 2, the outer ends of the levers will be carried outwardly and as said outer ends are connected to one of the clamp plates, said clamp. plate will be moved'laterally away from the other clamp plate.

I have provided ineans accessible from the top of the bed plate 1, "for controlling the relative position oi the levers of each pair,

thereby determining the initial position of the corresponding clamp plate.

For this purpose I have provided two rock shai't's 25, which extend through the bed plate, each of which carries at its lower end a positioning arm 24, which is adapted to engage the levers of one pair at the point where they are pivotally connected. upper end of each rock shaft 25, is provided with an arm having the thumb piece 27. There is one such arm and its connections for each clamp plate;

The spring 23 tends at all times to draw the clamp plates toward each other, and the positioning element 24 constitutes means for limiting the inward movement of the clamp plates, and thus determining their initial position, before the spreading action occurs.

Theconstruction above described provides a simple device by which the operator'may quickly and easily adjust the clamp plates as to their initial position and thus determine the amount or degree to which the clamp plates will be spread during the relative movement of theparts from buttonhole cutting test-itching position.

If the maximum spread is desired, then thearins 26 will be swung outwardly from the position shown in Fig. 1, this operation The turning the positioningmembers 24, so as to allow the connected ends of the levers 1618 to swing outwardly, and the inner end to swing inwardly under the influence of the spring This. brings the clamp plates closer together, so that when the rolls 12 engage the cam surfaces 11, a greater spreading action will result. On the other hand if it is desired to have a small amount of spreading, the lever will swing inwardly, which operation spreads the plates and gives them an initial position further apart, so that whenthe rolls 12 engage the surfaces ll, there will be less spreading movement.

By means of this construction the operator can adjust the clamp plates at any time by simply shifting the arms 26', and'lie is, therefore, able to instantly adjust his machine for different grades of goods.

I claim- 1. In a sewing machine having a bed plate, work-holding means carried thereby and comprising two clamp-plates capable of separating movement to spread the buttonhole slit, a throat plate, saidfwork-holdifig means and throat plate "having a relative movement from button-hole cutting tion to stitching position and'aspreader by which the clamp-plates are separated "to a predetermined point during such relative movement, the combination with said clampplates and spreadenof a positioning device for determining the initial position of each clamp-plate and'a swinging arm operating which each positioningdevice is adjusted. I

2.11141 sewing machine having {a bed plate, work-holding means carried thereby and comprising two clamp-plates capable of separating movement to spread the buttonhole slit, a throat plate, said work-holding means and throat plate having a relative movement from button-hole cutting position to stitching position, and a spreader by which the clamp-plates are spread'to a predetermined point during such relative movement, the combination with said spreader and clamp-plates, of two rock shafts extending through the bed plate, a positioning elenienton each rock shaft for determining the initial position of the corresponding,clampplate, and anarm for operating eachrock shaft located above the bed plate.

3. In a sewing machine having a. bed plate, Work-holding means carriedth'ereby and comprising two clamp plates capable of separating movement to spread the button-hole slit, a throat plate, said work-:

by which the clamp plates are separated to a predetermined point duringsuch relative movement, the combination with said clamp plates and spreader, of two pairs of pivotally-connected levers, one for each clamp plate, each pair of levers being connected to the corresponding plate, a positioning device acting on each pair of levers thereby to determine the initial position of the corresponding plate, and means for adjusting the position of the positioning device.

4:. In a sewing machine having a bed plate, work-holding means carried thereby and comprising two clamp plates capable of separating movement to spread the button-hole slit, a throat plate, said workholding means and throat plate having a relative movement from button-hole cutting position to stitching position and a spreader by which the clamp plates are separated to a predetermined point during such relative movement, the combination with said clamp plates and spreader, of two pairs of pivotally-connected levers, one for each clamp plate, each pair of levers being connected to the corresponding plate, a positioning device acting on each pair of levers thereby to determine the initial position of the corresponding plate, and a swinging arm above the bed plate for adjusting the position of each positioning device.

In testimony whereof, I have signed my name to this specification.

JOHN KIEWICZ. 

